Figure 5.

Implications of strain and delocalization on general reactivity. MLR plots for the prediction of ΔH^‡ from ΔH_r and n₃ for the hydrocarbon test set with CH₃^• (a) and NH₂^– (b) using eq 4. The blue dashed lines denote perfect correlation. (c) Increasing strain release driving force for [3.1.1]propellane (J) vs [1.1.1]propellane (H) counteracts the decrease in intrinsic reactivity due to a loss of bond delocalization, resulting in similar reactivity. (d) Addition of dibenzylamine to bicyclo[1.1.0]butane and bicyclo[2.1.0]pentane sulfones. Increased delocalisation lowers the required temperature for this reaction, opposing the expected behavior based on strain release energies alone. . (e) Selected examples of the synergy or antagonism between strain release and delocalization in the ring-opening reactivity of heterocycles. See the SI (Figures S9 and S10) for Marcus E_a values from refs (47) and (48) and the full data set of radical and anionic reactivity. All relative reaction rates were estimated at 298 K.